JP2003195487A - Transparent conductive paste, display member and plasma display panel using the paste, and method for manufacturing member for plasma display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide transparent conductive paste capable of simply forming an accurate fine pattern on a transparent conductive pattern to be formed, especially on a plasma display panel, a member for the plasma display panel, and a transparent electrode for a display member. <P>SOLUTION: The transparent conductive paste includes transparent conductive powder and an organic component containing a photoreaction compound. A display member and a transparent conductive pattern for a plasma display panel can be obtained by a simple manufacturing method for applying the transparent conductive paste and forming a pattern through exposure and development, and baking the pattern. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transparent conductive paste used for forming a transparent conductive pattern, a display member and a display using the same, and particularly to a plasma display panel, a plasma display panel member and a display. The present invention relates to a transparent conductive paste used for forming a transparent electrode of a member.

[0002]

2. Description of the Related Art Conventionally, the following method has been adopted as a method for forming a transparent conductive pattern. 1. 1. Screen printing method with a screen plate having a desired pattern interposed Vapor deposition with a mask having a desired pattern
Sputtering method 3. After forming a transparent conductive layer in the area including the desired pattern area on the substrate by various coating methods, vapor deposition / sputtering method, etc., a resist layer is formed, and then patterning, etching, resist A method of obtaining a desired pattern by peeling layers.

In recent years, in transparent conductive patterns, there is an increasing demand for higher positional accuracy, higher density, and higher definition, and accordingly, improvement of pattern processing technology is desired.
In particular, regarding the transparent electrode portion of the member for plasma display panel (PDP), unlike the circuit board, the pattern forming accuracy on a large-sized substrate having a diagonal of 20 to 40 inches or higher and higher definition can be achieved. Is desired.

In response to these demands, the screen printing method of 1 above inevitably causes bleeding and elongation of the screen plate. Even if the size of the screen mesh and the printing conditions are optimized, the width and height of the screen are reduced. It was difficult to improve the positional accuracy, and there was a limit to fine patterning.

The pattern vapor deposition / pattern sputtering method of the above-mentioned 2 gives better results than that of the above-mentioned 1, but since there is wraparound from the opening to the mask shielding portion, high density and high definition are required. There was a limit.

Therefore, as a method of responding to these demands, the above-mentioned three methods interposing a photo process are used.

[0007]

However, this method has a drawback in that the number of steps such as formation of the resist layer, patterning and etching of the resist layer, peeling of the resist layer, and the number of steps are very complicated.

Therefore, an object of the present invention is to provide a transparent conductive paste, particularly a plasma display panel, a member for a plasma display panel, a transparent electrode of a member for a display, which can easily form a fine pattern with high precision. And to provide a method for forming a transparent conductive pattern by a photo process that does not have the above-mentioned drawbacks.

[0009]

That is, the present invention provides a transparent conductive paste containing a transparent conductive powder and an organic component, wherein the transparent conductive paste contains at least a photoreactive compound as an organic component. is there. Also,
The present invention is a display member, a plasma display panel, and a method for manufacturing a display panel member using the same.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The transparent conductive paste of the present invention contains a transparent conductive powder and an organic component, and contains at least a photoreactive compound as the organic component. The transparent conductive paste of the present invention is preferably used when a pattern is formed by photolithography and then baked to form a pattern substantially made of an inorganic material.

The organic component contained in the transparent conductive paste of the present invention needs to contain at least a photoreactive compound, for example, a photoreactive monomer, a photoreactive oligomer, a photoreactive polymer and the like. Here, the reactivity means that when the photosensitive paste is exposed to actinic rays, the reactive monomer, the reactive oligomer, and the reactive polymer are photocrosslinked, photopolymerized, photodepolymerized, and photomodified. Means that the chemical structure changes through the reaction.

The photoreactive compound in the present invention preferably contains a copolymer having a carboxyl group. As the copolymer having a carboxyl group, for example, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, vinyl acetic acid or a carboxyl group-containing monomer such as an acid anhydride thereof and methacrylic acid ester, acrylic acid. Examples thereof include those obtained by selecting monomers such as acid ester, styrene, acrylonitrile, vinyl acetate, and 2-hydroxyacrylate, and copolymerizing them using an initiator such as azobisisobutyronitrile.

As the copolymer having a carboxyl group, a copolymer having a (meth) acrylic acid ester and a (meth) acrylic acid as a copolymerization component is preferably used because of its low thermal decomposition temperature during firing. Above all, a styrene / methyl methacrylate / methacrylic acid copolymer is preferably used.

The resin acid value of the copolymer having a carboxyl group is preferably 50 to 150 mgKOH / g. By setting the acid value to 150 mgKOH / g or less, it is possible to widen the development allowable range. Also, the acid value is 50m
By setting it to gKOH / g or more, the solubility of the unexposed area in the developing solution does not decrease, and therefore it is not necessary to increase the concentration of the developing solution and the exfoliation of the exposed area can be prevented, and a highly precise pattern can be obtained. .

Further, it is also preferred that the copolymer having a carboxyl group has an ethylenically unsaturated group in its side chain.
Examples of the ethylenically unsaturated group include an acrylic group, a methacrylic group, a vinyl group and an allyl group. The method of adding such a side chain to the copolymer is a mercapto group, an amino group, a hydroxyl group or a carboxyl group in the copolymer, an ethylenically unsaturated compound having a glycidyl group or an isocyanate group or acrylic acid chloride. , Methacrylic acid chloride or allyl chloride may be added to react.

Examples of the ethylenically unsaturated compound having a glycidyl group include glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, glycidyl ethyl acrylate, crotonyl glycidyl ether, crocidic glycidyl ether, and isocrotonic glycidyl ether. . Examples of the ethylenically unsaturated compound having an isocyanate group include (meth) acryloyl isocyanate and (meth) acryloyl ethyl isocyanate. Further, the ethylenically unsaturated compound having a glycidyl group or an isocyanate group, acrylic acid chloride, methacrylic acid chloride or allyl chloride is 0.05 to 1 mol with respect to the mercapto group, amino group, hydroxyl group or carboxyl group in the polymer. It is preferable to add the same amount. Further, the addition amount of the copolymer having a carboxyl group is 10 to 90% by weight in the organic component excluding the solvent in that an appropriate exposure amount can be obtained.
Is preferred.

Further, it is essential that the transparent conductive paste of the present invention contains a transparent conductive powder. Here, the transparent conductive powder has a visible light transmittance of 80% with respect to a thickness of 1 μm.
The above means a powder having conductivity.
Examples of such transparent conductive powder include powders mainly composed of transparent conductive metal oxides such as tin oxide, indium oxide, and indium tin oxide (ITO) which is a composite oxide thereof, and transparent glass powders. A powder obtained by coating a transparent non-conductive inorganic powder with these transparent conductive metal oxides is preferably used.

The transparent conductive powder is preferably contained in the paste in an amount of 10 to 60% by weight. It is more preferably in the range of 15 to 50% by weight. This is because it becomes easy to perform pattern processing on a substrate used for a normal display. Further, in the present invention, a transparent non-conductive inorganic powder can be further included. This makes it possible to achieve a pattern having a desired resistance value or an anisotropic conductive film by adjusting the pattern formation thickness and the ratio of the transparent conductive powder to the transparent non-conductive inorganic powder.

The average particle size of the transparent conductive powder is 10
It is preferably from nm to 500 nm. Thereby,
This is because a thin film pattern having a pattern formation thickness of 1 μm or less can be achieved. Particularly, by setting the average particle size of the transparent conductive powder to 10 nm to 100 nm, a thin film and a low resistance pattern can be achieved. In the present invention, the average particle size of the transparent conductive powder is measured by observing the transparent conductive powder in the paste with a scanning electron microscope, and measuring the diameter of the transparent conductive powder in the longitudinal direction to 10
Zero particles were measured, and the average value thereof was defined as the average particle diameter of the transparent conductive powder. In the observation, 100 particles whose diameter in the longitudinal direction could be confirmed and measured were selected, and transparent conductive powder which could not be confirmed because it overlapped with other powders was excluded from the object.

The transparent conductive paste of the present invention may further contain a photopolymerization initiator. The photopolymerization initiator is
It is used by selecting from those that generate radical species. As the photopolymerization initiator, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethylketal, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropane-
1-one, 4- (2-hydroxyethoxy) phenyl-
(2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexyl-phenyl ketone, 1-phenyl-
1,2-Propanedion-2- (o-ethoxycarbonyl) oxime, 2-methyl- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1 -(4-morpholinophenyl) -butanone-1, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzophenone, o-benzoyl methyl benzoate,
4-phenylbenzophenone, 4,4-dichlorobenzophenone, hydroxybenzophenone, 4-benzoyl-4′-methyl-diphenylsulfide, alkylated benzophenone, 3,3 ′, 4,4′-tetra (t-butylperoxycarbonyl) Benzophenone, 4-benzoyl-N, N-dimethyl-N- [2- (1-oxo-
2-Propenyloxy) ethyl] benzenemethanaminium bromide, (4-benzoylbenzyl) trimethylammonium chloride, 2-hydroxy-3- (4-benzoylphenoxy) -N, N, N-trimethyl-1-propenaminium chloride Monohydrate, 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,
4-diethylthioxanthone, 2,4-dichlorothioxanthone, 2-hydroxy-3- (3,4-dimethyl-)
9-oxo-9H-thioxanthene-2-yloxy)-
N, N, N-trimethyl-1-propanaminium chloride, 2,4,6-trimethylbenzoylphenylphosphine oxide, 2,2′-bis (o-chlorophenyl)
-4,5,4 ', 5'-Tetraphenyl-1,2-biimidazole, 10-butyl-2-chloroacridone, 2
- ethyl anthraquinone, benzyl, 9,10-phenanthrenequinone, camphorquinone, methyl phenylglyoxylate esters, eta ⁵ - cyclopentadienyl eta ⁶ -
Cumenyl-iron (1 +)-hexafluorophosphate (1-), diphenyl sulfide derivative, bis (η ⁵ -2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3- (1H- Pyrrole-1-
Yl) -phenyl) titanium, 4,4-bis (dimethylamino) benzophenone, 4,4-bis (diethylamino) benzophenone, thioxanthone, 2-methylthioxanthone, 2-chlorothioxanthone, 4-benzoyl-4-methylphenylketone, Dibenzyl ketone,
Fluorenone, 2,3-diethoxyacetophenone,
2,2-dimethoxy-2-phenyl-2-phenylacetophenone, 2-hydroxy-2-methylpropiophenone, pt-butyldichloroacetophenone, benzylmethoxyethyl acetal, anthraquinone, 2-t
-Butyl anthraquinone, 2-amino anthraquinone,
β-chloroanthraquinone, anthrone, benzanthrone, dibenzsuberone, methyleneanthrone, 4-azidobenzalacetophenone, 2,6-bis (p-azidobenzylidene) cyclohexane, 2,6-bis (p-
Azidobenzylidene) -4-methylcyclohexanone,
2-phenyl-1,2-butadion-2- (o-methoxycarbonyl) oxime, 1,3-diphenylpropanetrione-2- (o-ethoxycarbonyl) oxime,
Naphthalene sulphonyl chloride, quinoline sulfonyl chloride, N-phenylthioacridone, 4,4-
Azobisisobutyronitrile, benzthiazole disulfide, triphenylphosphine, carbon tetrabromide, tribromophenyl sulfone, benzoyl peroxide and eosin, photo-reducing dyes such as eosin and methylene blue, and reducing agents such as ascorbic acid and triethanolamine. And the like.

In the present invention, these may be used alone or in combination of two or more. The photopolymerization initiator is preferably 0.05 to 20% by weight, more preferably 0.1 to 20% by weight, based on the total amount of the organic components excluding the solvent. By setting the addition amount of the photopolymerization initiator within this range, good photosensitivity can be obtained while maintaining the residual ratio of the exposed portion.

By using a sensitizer together with the photopolymerization initiator, the sensitivity can be improved and the wavelength range effective for the reaction can be expanded. Specific examples of the sensitizer include 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone and 2
-Isopropylthioxanthone, 2,3-bis (4-diethylaminobenzal) cyclopentanone, 2,6-bis (4-dimethylaminobenzal) cyclohexanone,
2,6-bis (4-dimethylaminobenzal) -4-methylcyclohexanone, Michler's ketone, 4,4-bis (diethylamino) benzophenone, 4,4-bis (dimethylamino) chalcone, 4,4-bis (diethylamino) Chalcone, p-dimethylaminocinnamylidene indanone, p-dimethylaminobenzylidene indanone,
2- (p-dimethylaminophenylvinylene) isonaphthothiazole, 1,3-bis (4-dimethylaminophenylvinylene) isonaphthothiazole, 1,3-bis (4-dimethylaminobenzal) acetone, 1,3- Carbonylbis (4-diethylaminobenzal) acetone, 3,3-carbonylbis (7-diethylaminocoumarin), triethanolamine, methyldiethanolamine, triisopropanolamine, N-phenyl-N
-Ethylethanolamine, N-phenylethanolamine, N-tolyldiethanolamine, methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, isoamyl dimethylaminobenzoate, isoamyl diethylaminobenzoate, benzoic acid (2-dimethylamino ) Ethyl, (n-butoxy) ethyl 4-dimethylaminobenzoate, 2-ethylhexyl 4-dimethylaminobenzoate, 3-phenyl-5-benzoylthiotetrazole, 1-phenyl-5-ethoxycarbonylthiotetrazole and the like. .

In the present invention, these may be used alone or in combination of two or more. Some sensitizers can also be used as photopolymerization initiators. When the sensitizer is added to the photosensitive paste of the present invention, the addition amount is preferably 0.05 to 20% by weight in the total amount of the organic components excluding the solvent,
It is more preferably 0.1 to 20% by weight. By setting the addition amount of the sensitizer within this range, good photosensitivity can be obtained while maintaining the residual ratio of the exposed portion.

Further, in the present invention, an ultraviolet absorber is preferably added. By adding the ultraviolet absorber, the scattered light inside the paste due to the exposure light can be absorbed and the scattered light can be weakened. This makes it possible to form a finer pattern sharply, and therefore can be preferably used. As the ultraviolet absorber, those composed of organic dyes are preferably used. Specifically, azo dyes, aminoketone dyes, xanthene dyes, quinoline dyes, anthraquinone dyes, benzophenone dyes, diphenylcyanoacrylate dyes, triazine dyes, p-aminobenzoic acid dyes, etc. can be used. .
The organic dye is preferable because it does not remain in the insulating film after firing, and thus the deterioration of the insulating film characteristics due to the ultraviolet absorber can be suppressed. Among these, azo dyes and benzophenone dyes are preferable.

The addition amount of the ultraviolet absorber is preferably 0.001 to 2% by weight, more preferably 0.01 to 1% by weight, based on the total amount of the organic components excluding the solvent. This is because by setting it within this range, it is possible to keep the transmission limit wavelength and the wavelength inclination width within the desired range, and obtain the effect of absorbing scattered light while maintaining the transmittance of exposure light and the sensitivity of the photosensitive paste. .

The organic component of the present invention can also contain an amine compound having an ethylenically unsaturated group.
In that case, it is particularly preferable to contain an amine compound having an ethylenically unsaturated group represented by the following chemical formulas (1) and (2): R ¹ R ² R ³ N (1) R ¹ R ³ N -L-NR ² R ⁴ (2) (wherein R ³ and R ⁴ represent a substituent having an ethylenically unsaturated group, R ¹ and R ² are a substituent having an ethylenically unsaturated group, a hydrogen atom Represents a group selected from an alkyl group having 1 to 20 carbon atoms, an aryl group, an aralkyl group, and a hydroxyalkyl group, R ¹ and R ² may be the same or different, and L is a divalent linkage. Among the amine compounds preferably used in the present invention, the above formula (1)
Examples of the compound represented by the formula (1) include those having one ethylenically unsaturated group in the molecule, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N -Dimethylaminopropyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, (meth) acroylmorpholine,
N-isopropyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N- [3- (N ',
One or more selected from N′-dimethylamino) propyl] (meth) acrylamide, vinyl p-dimethylaminobenzoate, vinylpyridine, allylamine and allylaniline can also be preferably used.

Further, as the amine compound represented by the above formula (1), bis (2-hydroxy-3-methacryloyloxypropyl) isopropylamine, bis (2-hydroxy-3-methacryloyloxypropyl) isopropylamine, or bis (2-hydroxy-3-methacryloyloxypropyl) isopropylamine is one having two ethylenically unsaturated groups in the molecule. One or more selected from (2-hydroxy-3-methacryloyloxypropyl) normal propyl amine and diallyl amine can also be preferably used.

Further, as the amine compound represented by the above formula (1), tris (2-methacryloyloxyethyl) amine and tris (2-hydroxy) can be used as those having three or more ethylenically unsaturated groups in the molecule. One or more selected from -3-methacryloyloxypropyl) amine and triallylamine can also be preferably used.

Among the amine compounds preferably used in the present invention, as the compound represented by the above formula (2),
Those having one ethylenically unsaturated group in the molecule include N- (2-hydroxy-3-methacryloyloxypropyl) polyoxypropylenediamine and N- (2-
Methacryloyloxyethyl) polyoxyethylenediamine, N- (2-methacryloyloxyethyl) ethylenediamine, N- (2-methacryloyloxyethyl)
One or more selected from -N ', N'-dimethylethylenediamine can also be preferably used.

The compound represented by the above formula (2) containing two ethylenically unsaturated groups in the molecule is
N, N-bis (2-hydroxy-3-methacryloyloxypropyl) polyoxypropylenediamine, N,
One or more selected from N'-bis (2-methacryloyloxyethyl) polyoxyethylenediamine can also be preferably used.

As the compound represented by the above formula (2), a compound containing three ethylenically unsaturated groups in the molecule is:
N, N, N'-tris (2-hydroxy-3-methacryloxypropyl) polyoxypropylenediamine, N,
N, N'-tris (2-methacryloyloxyethyl)
One or more selected from polyoxyethylenediamine and N, N, N'-tris (2-methacryloyloxyethyl) -N'-methylpolyoxyethylenediamine can also be preferably used.

The compound represented by the above formula (2) containing four or more ethylenically unsaturated groups in the molecule is N, N, N ', N'-tetra (2-methacryloyloxyethyl). ) Polyoxypropylenediamine, N,
One or more selected from N, N ′, N′-tetra (2-hydroxy-3-methacryloxypropyl) polyoxyethylenediamine can also be preferably used.

The preparation of the amine compound having an ethylenically unsaturated bond is carried out by glycidyl (meth) acrylate having an ethylenically unsaturated bond, (meth) acrylic acid chloride,
(Meth) acrylic acid anhydride or the like may be reacted with the amino compound. A plurality of ethylenically unsaturated group-containing compounds may be mixed and used. Examples of the amine compound having an ethylenically unsaturated bond include the compounds described above, but are not limited thereto. Also, these compounds may be used as a mixture.

In the present invention, a monomer having an ethylenically unsaturated bond other than the above amine compound may be used if necessary. Examples of such a polymerizable monomer include a monomer having one or more photopolymerizable (meth) acrylate groups or allyl groups. Specific examples thereof include acrylic acid or methacrylic acid ester of alcohols (eg, ethanol, propanol, hexanol, octanol, cyclohexanol, glycerin, trimethylolpropane, pentaerythritol, etc.), carboxylic acid (eg, acetic acid, propionic acid, benzoic acid). Acid, acrylic acid, methacrylic acid, succinic acid, maleic acid, phthalic acid, tartaric acid, citric acid, etc.) with glycidyl acrylate, glycidyl methacrylate, allyl glycidyl, or tetraglycidyl metaxylylenediamine, amide derivative (For example, acrylamide, methacrylamide, N-methylolacrylamide, methylenebisacrylamide, etc.), a reaction product of an epoxy compound with acrylic acid or methacrylic acid, and the like. Kill. In the polyfunctional monomer, the unsaturated group may be a mixture of acryl, methacryl, vinyl and allyl groups. These may be used alone or in combination.

An organic solvent is often used to adjust the viscosity when the paste is applied to the substrate according to the application method. As the organic solvent used at this time, methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl ethyl ketone, dioxane, acetone, cyclohexanone, cyclopentanone, isobutyl alcohol, isopropyl alcohol, tetrahydrofuran, dimethyl sulfoxide, γ-butyrolactone, bromobenzene, Chlorobenzene, dibromobenzene, dichlorobenzene,
Bromobenzoic acid, chlorobenzoic acid, etc., and an organic solvent mixture containing one or more of them are used.

In a photosensitive paste such as the transparent conductive paste of the present invention, it is usually difficult to avoid light scattering inside the paste due to exposure light due to the difference in the refractive index between the fine particles to be dispersed and the organic component. The shape is likely to be thickened and the pattern is filled (residual film formation), and is likely to be affected in a finer and finer pattern.

Therefore, in the present invention, a polymerization inhibitor is preferably added. By adding the polymerization inhibitor, it is possible to suppress a certain amount of radical polymerization, which occurs in the paste due to exposure light, depending on the type of the polymerization inhibitor and the addition amount thereof. This makes it possible to suppress photoreaction to weak light such as scattered light. Therefore, a finer pattern can be formed sharply, which is preferably used. The polymerization inhibitor in the present invention is not particularly limited as long as it can be used as a polymerization inhibitor, and examples thereof include p-benzoquinone, naphthoquinone,
Para-xyloquinone, para-toluquinone, 2,6-dichloroquinone, 2,5-diacetoxy-p-benzoquinone, 2,5-dicaproxyquino-p-benzoquinone, 2,
5-diaeroxy-p-benzoquinone, hydroquinone,
pt-butylcatechol, 2,5-dibutylhydroquinone, mono-t-butylhydroquinone, 2,5-di-t
-Amylhydroquinone, di-t-butyl paracresol, hydroquinone monomethyl ether, α-naphthol, acetanidin acetate, hydrazine hydrochloride, trimethylbenzylammonium chloride, trimethylbenzylammonium oxalate, phenyl-β-naphthylamine, parabenzyl Amininophenol, di-β
-Naphthylparaphenylenediamine, dinitrobenzene, trinitrobenzene, picric acid, quinone dioxime, cyclohexanoone oxime, pyrogallol, tannic acid, resormine, triethylamine hydrochloride, dimethylaniline hydrochloride, cuperon and the like.

The amount of the polymerization inhibitor added is preferably 0.001 to 3% by weight, more preferably 0.01 to 2% by weight, based on the total amount of the organic components excluding the solvent. If the amount is less than this range, the effect of inhibiting the polymerization is not exhibited, and even if the exposure amount is low due to light scattering, the composition is cured and the pattern shape is likely to be thickened. Further, if the amount is more than this range, the sensitivity is lowered and a large amount of exposure is required.

Further, in the exposure-development process, it is ideal that a sharp pattern is formed by being dissolved in a developing solution below a certain exposure amount and being insoluble in a developing solution above that. That is, it is preferable that even if the resin is cured with a low exposure amount due to light scattering, it dissolves in the developing solution, the thickening of the pattern shape and the filling between the patterns are eliminated, and a wide range in which resolution is possible even if the exposure amount is increased. Ideally, it dissolves in the developing solution below a certain exposure amount, and becomes insoluble in the developing solution above it.

In this respect, it is useful to add an antioxidant. The antioxidant has a radical chain inhibiting action, a triplet eliminating action, and a hydroperoxide decomposing action.

When an antioxidant is added to the photosensitive paste, the antioxidant traps radicals and returns the energy state of the excited photopolymerization initiator or sensitizer to the ground state, which causes scattered light. Excessive photoreaction is suppressed, and the photoreaction abruptly occurs at the exposure amount that cannot be suppressed by the antioxidant, so that the contrast of dissolution and insolubility in the developer can be increased.

Specifically, p-benzoquinone, naphthoquinone, p-xyloquinone, p-toluquinone, 2,6-dichloroquinone, 2,5-diacetoxy-p-benzoquinone, 2,5-dicaproxy-p-benzoquinone, hydroquinone. , Pt-butylcatechol, 2,5-dibutylhydroquinone, mono-t-butylhydroquinone, 2,5
-Di-t-amylhydroquinone, di-t-butyl-p-
Cresol, hydroquinone monomethyl ether, α-naphthol, hydrazine hydrochloride, trimethylbenzylammonium chloride, trimethylbenzylammonium oxalate, phenyl-β-naphthylamine, parabenzylaminophenol, di-β-naphthylparaphenylenediamine, dinitrobenzene, tri Nitrobenzene,
Picric acid, quinone dioxime, cyclohexanone oxime, pyrogallol, tannic acid, triethylamine hydrochloride, dimethylaniline hydrochloride, cuperone, (2,2 '
-Thiobis (4-t-octylphenolate) -2-ethylhexylaminonickel- (II), 4,4'-thiobis- (3-methyl-6-t-butylphenol),
2,2'-methylenebis- (4-methyl-6-t-butylphenol), 2,2'-thiobis- (4-methyl-
6-t-butylphenol), triethyleneglycol-bis [3- (t-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [(3,5-di-t-). Butyl-4-hydroxyphenyl) propionate], 1,2,3-trihydroxybenzene, and the like, but are not limited thereto. In the present invention, one or more of these may be used.

The amount of the antioxidant added is preferably 0.01 to 10% by weight, more preferably 0.1 to 5% by weight, based on the total amount of the organic components excluding the solvent. By keeping the amount of the antioxidant added within this range, the photosensitivity of the photosensitive paste is maintained, and while maintaining the degree of polymerization and the pattern shape, it is possible to increase the contrast of dissolution and insolubility in the developing solution. You can

In the transparent conductive paste of the present invention, if necessary, a photoacid generator, a photobase generator, a sensitization aid, a dispersant,
Additive components such as plasticizers, thickeners, organic solvents, acids, bases, antisettling agents, antioxidants and the like can be added.

For example, when a binder component is required, the polymer such as polyvinyl alcohol,
Polyvinyl butyral, methacrylic acid ester polymer,
Acrylic acid ester polymers, acrylic acid ester-methacrylic acid ester copolymers, butyl methacrylate resins and the like can be used.

The transparent conductive paste of the present invention contains various components such as the above-mentioned transparent conductive powder, transparent non-conductive inorganic powder, photosensitive organic component, binder component, photopolymerization initiator, and organic solvent in a predetermined composition. After mixing so that 3
It is prepared by uniformly mixing and dispersing with this roller or a kneader.

The viscosity of the paste is appropriately adjusted by the addition ratio of transparent conductive powder, transparent non-conductive inorganic powder, thickener, organic solvent, plasticizer, anti-settling agent, etc., but the range is usually 10 to 10. It is 200,000 cps (centimeter poise). For example, when the substrate is coated by a spin coating method, a dip coating method, or a spraying method, it is 10 to 5000.
cps is preferred. 5 when using screen printing
000 to 200,000 cps is preferable. When using a blade coater method, a die coater method, or the like, 5000 to 50,000 cps is preferable.

The transparent conductive paste of the present invention thus obtained can be preferably used for forming a member for a display. Particularly when used as a member for a plasma display panel, a transparent conductive paste of the present invention may be applied onto a substrate, exposed and developed to form a pattern, and then baked to obtain a pattern substantially composed of an inorganic substance. it can.

In addition, the substantially inorganic pattern produced by using the transparent conductive paste of the present invention can be suitably used as a transparent electrode of a plasma display panel front plate in display applications, particularly plasma display panel applications.

An example of patterning using the transparent conductive paste of the present invention will be described below, but the present invention is not limited to this. The transparent conductive paste of the present invention is applied on the entire surface or partially on the substrate. As a coating method, a screen printing method, a bar coater, a roll coater, a die coater, a blade coater, or the like can be used. The coating thickness can be adjusted by selecting the number of coatings, the screen mesh, and the viscosity of the paste.

Here, when the paste is applied to the substrate,
Surface treatment of the substrate can be performed in order to enhance the adhesion between the substrate and the coating film. As the surface treatment liquid, a silane coupling agent, for example, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, tris (2-methoxyethoxy) vinylsilane, γ-glycidoxypropyltrimethoxysilane, γ- (methacrylic acid). Roxypropyl) trimethoxysilane, γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, or an organic metal such as , Organic titanium,
Examples include organic aluminum and organic zirconium. A silane coupling agent or an organic metal diluted with an organic solvent such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl alcohol, ethyl alcohol, propyl alcohol or butyl alcohol to a concentration of 0.1 to 5%. To use.
Next, the surface treatment can be performed by uniformly applying the surface treatment solution onto the substrate with a spinner or the like and then drying at 80 to 140 ° C. for 10 to 60 minutes.

After coating, exposure is performed using an exposure device. As the exposure device, a proximity exposure device or the like can be used. When exposing a large area,
By applying the transparent conductive paste of the present invention on a substrate and then performing exposure while transporting, a large area can be exposed by an exposure device having a small exposure area.

After the exposure, the development is carried out by utilizing the difference in solubility between the exposed portion and the unexposed portion in the developing solution. In this case, the dipping method, the spray method or the brush method is used. It is preferable that the developing solution used for the developing treatment contains water as a main component in terms of cost and environmental load. As the developing solution, an organic solvent capable of dissolving the organic component in the transparent conductive paste of the present invention can be used. Examples include alcohols such as ethyl alcohol and methyl alcohol. Further, water may be added to the organic solvent within the range in which the dissolving power is not lost.

When a compound having an acidic group such as a carboxyl group is present in the photosensitive paste, it can be developed with an aqueous alkali solution. As the alkaline aqueous solution, sodium hydroxide, sodium carbonate, calcium hydroxide aqueous solution or the like can be used, but it is preferable to use the organic alkaline aqueous solution because the alkaline component can be easily removed during firing. As the organic alkali, a general amine compound can be used. Specific examples include tetramethylammonium hydroxide, trimethylbenzylammonium hydroxide, monoethanolamine and diethanolamine.

The concentration of the alkaline aqueous solution is usually 0.05 to 5
%, More preferably 0.1 to 1% by weight. If the alkali concentration is too low, the soluble portion is not removed. If the alkali concentration is too high, the pattern portion may be peeled off and the non-soluble portion may be corroded, which is not good. The development temperature during development is preferably 20 to 50 ° C. for process control.

Next, firing is performed in a firing furnace. The firing atmosphere and temperature vary depending on the type of paste or substrate, but firing is performed in an atmosphere of air, nitrogen, hydrogen or the like. As the firing furnace, a batch firing furnace or a belt type continuous firing furnace can be used.

The firing is usually carried out at 400 to 1000 ° C. When patterning on a glass substrate, 480-610
It is preferable to carry out the firing while maintaining the temperature at 10 ° C for 10 to 120 minutes.

[0058]

EXAMPLES The present invention will be specifically described below with reference to examples. However, the present invention is not limited to this. Unless otherwise specified, the concentration (%) in the examples is% by weight.
Is. (Measurement Method of Average Particle Diameter) The powder to be measured is observed with a scanning electron microscope (S-2400 manufactured by Hitachi, Ltd.), 100 diameters in the longitudinal direction of the powder to be measured are measured, and the average value is obtained. The average particle diameter of the powder to be measured was used. In the observation, 100 powders that can be confirmed and measured in the longitudinal direction of the measured powder were selected, and the measured powders that could not be confirmed because they overlapped with other powders were excluded from the target.

Organic component A excluding solvent: 57 parts by weight of a photosensitive monomer (trimethylolpropane triacrylate), 100 parts by weight of a photosensitive polymer (X-4007), a photopolymerization initiator (2-methyl-1) -[4- (Methylthio) phenyl] -2-morpholino-propanone-
1) 35 parts by weight Organic component B excluding solvent: Photosensitive polymer (X-400
7) 57 parts by weight of a photosensitive monomer (trimethylolpropane triacrylate), and a photopolymerization initiator (2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propanone-1) per 100 parts by weight. ) 35 parts by weight, photopolymerization inhibitor (hydroquinone monomethyl ether) 0.8 parts by weight Organic component excluding solvent C: Photosensitive polymer (X-400
7) 57 parts by weight of a photosensitive monomer (trimethylolpropane triacrylate), and a photopolymerization initiator (2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propanone-1) per 100 parts by weight. ) 35 parts by weight, UV absorber (organic dye: Basic Blue 7)
0.1 parts by weight of X-4007: 40% methacrylic acid, 30% methyl methacrylate, 30% styrene A carboxyl group and ethylenic group obtained by addition-polymerizing 0.4 equivalent of glycidyl methacrylate with respect to the carboxyl group of a styrene copolymer. A polymer having an unsaturated group and a weight average molecular weight of 43,000 and an acid value of 95.

(Example 1) First, a front plate was produced. 50% of ITO powder (PASSTRAN) manufactured by Mitsui Kinzoku Co., Ltd., which is a transparent conductive powder having an average particle diameter of 1 μm, 20% of organic component A excluding the solvent, and 30% of γ-butyrolactone as an organic solvent are dissolved and mixed. It was dispersed and uniformly kneaded with a kneader to prepare a transparent conductive paste. The paste viscosity was 5000 cps.

This transparent conductive paste was applied onto a glass substrate "PD200" manufactured by Asahi Glass Co., Ltd. by a screen printing method using a 420 mesh polyester screen printing plate, and then the coating film was dried at 80 ° C. for 40 minutes. did. After drying, the thickness was 3 μm.

Ultraviolet exposure was performed for about 30 seconds with an ultrahigh pressure mercury lamp with an output of 15 mW / cm ² through a negative type photomask having a scan electrode pattern having a pitch of 375 μm and a line width of 150 μm. The development was carried out in a shower of a 30% monoethanolamine 0.2% aqueous solution to remove the unexposed portion. Then, the remaining developing solution was washed away with a pure water shower and dried at 80 ° C. for 20 minutes. The firing was performed by raising the temperature at a rate of 250 ° C./hour and maintaining the maximum temperature of 590 ° C. for 60 minutes. Thus, there is no pinhole or disconnection, thickness 1.6 μm, pitch 375 μm, line width 150 μm, sheet resistance value 25 Ω / □, specific resistance value 40.
A high-definition scan electrode with Ω · cm was obtained.

Further, a photosensitive silver paste was applied on the substrate, and similarly, mask exposure through a photomask,
Development using 0.3% sodium carbonate aqueous solution, 580 ° C
After baking for 15 minutes, line width 50μm, thickness 3μm
The bus electrode of was formed.

Next, a glass paste obtained by kneading 70% of a low melting point glass powder containing 75% by weight of lead oxide, 20% of ethyl cellulose and 10% of terpineol was screen-printed to obtain a bus electrode in the display area. To a thickness of 20 μm to cover
A front dielectric was formed by firing for 15 minutes. The thickness of 0.5 is obtained by electron beam evaporation on the substrate on which the dielectric is formed.
A μm magnesium oxide layer was formed to prepare a front plate.

Next, a back plate was manufactured in the following manner.
Address electrodes were formed on "PD200" by using a photosensitive silver paste method. That is, a line width of 50 μm is obtained by applying a photosensitive silver paste, drying, exposing, developing, and baking steps.
m, thickness 3 μm, pitch 250 μm, address electrodes were formed. Subsequently, a glass paste obtained by kneading 60% of a low-melting glass powder containing 75% by weight of bismuth oxide, 10% of titanium oxide powder having an average particle diameter of 0.3 μm, 15% of ethyl cellulose, and 15% of terpineol. Was applied by screen printing to a thickness of 20 μm, and then baked at 570 ° C. for 15 minutes to form a back dielectric layer. Partition walls were formed on the dielectric layer by a photosensitive paste method. After applying the photosensitive paste, it was exposed using a photomask having a line width of 30 μm in the opening, and then developed in an aqueous solution of 0.5% by weight of ethanolamine.
By firing for 15 minutes at 60 ℃, pitch 250μ
m, a line width of 30 μm, and a height of 130 μm were formed.

Next, a phosphor was applied between the adjacent partition walls. The phosphor is applied at 64 holes (caliber: 130μ).
m) was formed by a dispenser method in which the phosphor paste was discharged from the tip of the nozzle. The phosphor has a thickness of 25 μm after firing on the side walls of the partition wall and a thickness of 25 μ after firing on the dielectric.
After coating so as to have a thickness of m, baking was performed at 500 ° C. for 10 minutes to complete the back plate. The front plate and the back plate were sealed using a sealing glass, and Ne gas containing 5% Xe was sealed so that the internal gas pressure was 66500 Pa. The manufactured PDP was driven normally over the entire surface.

(Example 2) As a transparent conductive powder, an ITO powder having an average particle diameter of 18 nm (manufactured by Mitsui Kinzoku Co., Ltd .: PA)
Example 1 was repeated except that SSTRAN) was used to prepare a PDP. The scan electrode on the front plate has a thickness of 1.6 μm, a sheet resistance value of 20Ω / □, and a specific resistance value of 32Ω.
Cm, sheet resistance value and specific resistance value were reduced by about 20%, and the manufactured PDP was driven normally over the entire surface.

Example 3 A PD was prepared by repeating Example 1 except that the scan electrodes on the front plate were manufactured by the following method.
P was prepared. The average particle size of the transparent conductive powder is 18
35% of the ITO powder of 25 nm, 25% of the organic component A excluding the solvent and 40% of the organic solvent (γ-butyrolactone) were dissolved, mixed and dispersed, and uniformly kneaded with a kneader to prepare a transparent conductive paste. The paste viscosity was 500 cps. This transparent conductive paste is used as a glass substrate P manufactured by Asahi Glass Co., Ltd.
Coating was performed on D200 by a spin coater method, and then the coating film was dried at 80 ° C. for 40 minutes. Thickness after drying is 2μ
It was m.

Scan electrode pattern (pitch 375 μ
m, a negative UV exposure of about 30 seconds at an ultra-high pressure mercury lamp with an output 15 mW / cm ² through a photomask having a line width 150 [mu] m) was performed. The development was carried out in a shower of a 30% monoethanolamine 0.2% aqueous solution to remove the unexposed portion. Then, the remaining developing solution was washed away with a pure water shower and dried at 80 ° C. for 20 minutes.
The firing temperature is raised at a rate of 250 ° C./hour, and the maximum temperature is 590.
It hold | maintained at 60 degreeC for 60 minutes, and performed.

The thickness of the scan electrode of the front plate thus obtained was 1.0 μm, the sheet resistance value was 32 Ω / □, and the specific resistance value was 32 Ω · cm. Since the specific resistance value could be reduced by about 20%, the scan electrode thickness was The sheet resistance value slightly increased (about 10%) even when the thickness was reduced, and the manufactured PDP was driven normally over the entire surface.

Example 4 A PDP was prepared by repeating Example 1 except that the organic component B excluding the solvent was used as the organic component excluding the solvent in the transparent conductive paste. The edges of the scan electrodes on the front plate were sharpened, and as compared with Example 1, scan electrodes with less variation in the width of the leading edge were obtained with high accuracy. Moreover, the manufactured PDP was driven normally over the entire surface.

Example 5 A PDP was produced by repeating Example 3 except that the organic component B excluding the solvent was used as the organic component excluding the solvent in the transparent conductive paste. The edges of the scan electrodes on the front plate were sharpened, and scan electrodes with less variation in the width of the leading edge were obtained with high accuracy as compared with Example 3. Moreover, the manufactured PDP was driven normally over the entire surface.

Example 6 A PDP was manufactured by repeating Example 1 except that the organic component C excluding the solvent was used as the organic component excluding the solvent in the transparent conductive paste. The edges of the scan electrodes on the front plate were sharpened, and as compared with Example 1, scan electrodes with less variation in the width of the leading edge were obtained with high accuracy. Moreover, the manufactured PDP was driven normally over the entire surface.

Example 7 A PDP was produced by repeating Example 3 except that the organic component C excluding the solvent was used as the organic component excluding the solvent in the transparent conductive paste. The edges of the scan electrodes on the front plate were sharpened, and scan electrodes with less variation in the width of the leading edge were obtained with high accuracy as compared with Example 3. Moreover, the manufactured PDP was driven normally over the entire surface.

(Example 8) A PDP was manufactured by repeating Example 3 except that a transparent conductive paste having the following composition was prepared. 20% of ITO powder having an average particle diameter of 18 nm as a transparent conductive powder, 15% of organic component A excluding the solvent
And 65% of organic solvent (γ-butyrolactone) are dissolved.
A transparent conductive paste was prepared by mixing / dispersing and uniformly kneading with a kneader. The paste viscosity was 50 cps. The thickness of the scan electrode on the front plate thus obtained is 0.5 μm.
It was m. The manufactured PDP was driven normally over the entire surface.

(Example 9) A PDP was manufactured by repeating Example 3 except that a transparent conductive paste having the following composition was prepared. As transparent conductive powder, 10% of ITO powder having an average particle diameter of 18 nm, 7% of organic component A excluding solvent and 83% of organic solvent (γ-butyrolactone) are dissolved / mixed / dispersed and homogeneously kneaded by a kneader. Then, a transparent conductive paste was prepared. The paste viscosity was 10 cps. The thickness of the scan electrode of the front plate thus obtained is 0.2 μm.
Therefore, the resistance value per transparent electrode was large, and more electric power was required to drive the manufactured PDP over the entire surface.

(Example 10) A PDP was manufactured by repeating Example 1 except that a transparent conductive paste having the following composition was manufactured. As transparent conductive powder, 60% of ITO powder having an average particle size of 1 μm and 25% of organic component A excluding solvent
And 15% of organic solvent (γ-butyrolactone) are dissolved.
A transparent conductive paste was prepared by mixing / dispersing and uniformly kneading with a kneader. The paste viscosity was 25000 cps.

The thickness of the scan electrode of the front plate thus obtained was 2.2 μm, and although the manufactured PDP was driven over the entire surface, the transparency of the scan electrode was lowered and the brightness was lowered.

Comparative Example 1 60% of ITO powder having an average particle size of 1 μm as a transparent conductive powder, 25% of an organic component (ethyl cellulose) excluding the solvent and 15% of an organic solvent (terpineol) are dissolved and mixed. It was dispersed and uniformly kneaded with a kneader to prepare a transparent conductive paste. The paste viscosity was 30,000 cps.

This transparent conductive paste was applied on a glass substrate "PD200" manufactured by Asahi Glass Co., Ltd., with a pitch of 375 μm and a line width of 15
Pattern printing was performed by a screen printing method using a 420-mesh polyester screen printing plate for pattern formation of 0 μm, and then the coating film was dried at 80 ° C. for 40 minutes. After drying, the thickness was 3 μm. Next, firing was performed by raising the temperature at a rate of 250 ° C./hour and maintaining the maximum temperature of 590 ° C. for 60 minutes.

Since the obtained scan electrode pattern suffered from uneven pattern thickening due to printing bleeding, the line width varied greatly, and a scan electrode that could be used practically could not be obtained.

[0082]

With the paste of the present invention, high positional accuracy,
It is possible to form a high-density, high-definition transparent conductive pattern. Further, it is possible to provide a display member and a PDP in which the transparent conductive pattern itself is produced by a photo process.

Continued front page    F term (reference) 2H025 AA02 AA04 AB14 AB20 AC01                       AD01 BC13 BC42 BC53 BC85                       CA00 CB13 CB43 CC02 CC09                       FA17 FA29                 2H096 AA27 AA30 BA05 BA06 EA02                       GA08 HA01                 5C027 AA01                 5C040 GC18 GC19 JA15

Claims (15)

[Claims] 1. A transparent conductive paste containing transparent conductive powder and an organic component, which contains at least a photoreactive compound as an organic component. 2. The transparent conductive paste according to claim 1, wherein the photoreactive compound contains a copolymer having a carboxyl group. 3. The transparent conductive paste according to claim 1, wherein the photoreactive compound contains an ethylenically unsaturated group. 4. The transparent conductive paste according to claim 1, wherein the photoreactive compound contains an acrylic acid ester compound or a methacrylic acid ester compound. 5. The transparent conductive paste according to claim 1, wherein the transparent conductive powder contains at least one of tin oxide and indium oxide. 6. The transparent conductive paste according to claim 1, wherein the content of the transparent conductive powder in the transparent conductive paste is in the range of 10 to 60% by weight. 7. The transparent conductive powder has an average particle size of 10 to 50.
It is in the range of 0 nm, The transparent conductive paste of Claim 1 characterized by the above-mentioned. 8. The transparent conductive paste according to claim 1, further comprising a photopolymerization inhibitor. 9. The transparent conductive paste according to claim 8, wherein the photopolymerization inhibitor is contained in an amount of 0.001 to 3% by weight in the total amount of the organic components excluding the solvent. 10. The transparent conductive paste according to claim 1, further containing an ultraviolet absorber. 11. The transparent conductive paste according to claim 10, wherein the ultraviolet absorber is contained in an amount of 0.001 to 2% by weight in the total amount of the organic components excluding the solvent. 12. The transparent conductive paste according to claim 1, which is used for forming a transparent electrode of a display member. 13. A display member comprising the transparent conductive paste according to any one of claims 1 to 12. 14. A plasma display panel comprising the transparent conductive paste according to claim 1. 15. A method for producing a member for a display panel, which comprises applying the transparent conductive paste according to any one of claims 1 to 12 onto a substrate, forming a pattern by exposure and development, and then baking. .